Disazo dyestuffs and method of preparing same



Patented Apr. 18,

LQU ITEDT S A E or WE TMINSTER. ENGLAND :Qiar'sub mimscrnrns METHOD OF rnnrenkmo sea'm This'invention relateslto the orange disazo dyestufisand the method of preparation of the same. More particularly it relates to dyes madebyhcoupling tetrazotized m:mtolidine with one molecular proportion'of salicylic acid and with onemol'ecular proportion of a compoundhoflth'enaphthalene series capable of coupling with-,diazo compounds. i f; V

It is knownthat the disazo derivativesof m; m tolidine (2 :7'2.- dimethyl-4 :4'5 diaminodiph'enyl) have much lessaflinity for hotton than those derived irombenzidinei and its 3 3'-su-bstituted derivatives (dianisidine, tolidine, etc.-).. See Fierz-David- Kunstliche organische Fabstofie Berlin 1926 p. 180 line 5flt'. and su'ch'dyestufls accordingly have received little attention and have been of little practical importance. In British patent specifications Nos. 10331. and 2867 8 of1 910ce1'tain of such dyestuffs have however been described.

' fIG the object of thepresent invention to "prepare from m; m -tolidine dyestufis yielding yellowish to reddishiorange dyeings characterized excellent fastness to washing; alkaline milling, "and :stoVing, and

The general formula covering broadly these dyes maybe represented as follows :1

which Rjr'epresents an aromatic radical which level 'wel'l an dare very .fast to alkaample #1 is probably 1 characterized further by goodievelling prop- H a v erties. T v f --These objects areaccomplishedby coupling tetrazotized m:m-toli dine '(2:2--di- 'methyl-4:eP-diaminodiphenyl) with :one molecular proportionbf salicylic acid and with-one molecularproportion of either 2- naphthol, ;'2-naphthol-1nonosulphonic acid,

2-naphthylamine-fi-sulphonic acid, ;-or 2- methyl-aminonaphthalene 7 sulphonic acid.

' stch-ebm dund age-naphthalene as who sulphonic acids, 3 Z-naphthylaniihe-G-sfllphonic acid, and .2-methyl-aminol-naphthalene-7-sulphonic acid.

My invention is illustrated by the following examples, wei ht.-

added. "Theflmix ture is stirred-and maintained cold and alkaline juntil combination is complete when the coupling ishea-ted up I;

and the dyestufi precipitated by the addition powder which dyes wool in orange shades.

line milling,ito'stoving and to light. The formula for the dye obtained by Ezr- OH: czo'om .N=N 011:: L r

IsoaNa 1 {Emcmiple 2. -T o the solution of tetraz o compound prepared from 212 parts ofim':

tolidine with 138 parts of'sodium nitrite.

and 500 parts of 36% hydrochloric acid there is added a solution containing 223 parts of 2 naphthylarnine- 6 sulphon icfl acid. "After stirring is maintained cold, is'made alkaline by the addition of about 500 parts of sodium carbonate and asolution of 160 parts of sodium PATENT ol -Fl es 3111mm) mmmm, m2 ENGLAND, ASSIG-NOB r0 mini cum-i5 Q in Drawing: iis mgetqimea highs: -6, 1930, Serial No.,473-,512;"tnu in Great Britain August 15, 1929.

2:2-dimethyldiphenyl :are tetrazotized in p the known manner with .138 parts" of acid. The itetrazo solution is stirred into a salicylic acid and 500 parts of s'odium carof common salt. It forms a yellowish. red

forsome time the mixture; which 7 salicylate is then added. mixture is stirred until coupling isioomplete when it is heated up and the dyestufi isolated by. the

. Salicylic acid;

acid addition of common salt. It dyes wool and orange yellow shade very fast to alkaline milling.

The formula for the dye obtained by Example #2 is probably C H; CO ONa 11: HaN

. SOsNa The invention is further illustrated by the examples in the following table m m'-tolidine tetrazotized and coupled with l Shade on wool (1) l (2) 1 molecule of 1 molecule of methyl 2 naphthy- Brownish-orange lamino 7 sulphonic acid F acid 2 naphthol 6 sulphonic acid Orange i Reddish-orange Scarlet Salicylic acid Salicylic acid Methyl 2 naphthyl amine 7 7 sulphonic It will be noted from Examples 1 and 2 that in each instance the couplings with "salicylic acid are carried out in alkaline reactions. Obviously, however, the examples are furnished by way of illustration merely --acterized I by excellent levelling properties.

They may, moreover, be used for silk, felt and like materials.

It will be understood that, while the formulas given herein inall probability cor rectly represent the dyes of the present invention, the invention is wholly independent of the correctness of such formulas.

As many apparentlywidely different embodiments of this invention may be made without departing from the spirit thereof, it is to be understood that I do not limit myself to. the foregoing examples or descriptions except'as indicatedin the following patent.

claims.

, I claim:

1. An orange disazo dyestuff represented by the following general formula V on: 10cm.

in which R represents a radical of the naphthalene series capable of coupling with diazo compounds, comprising a residue of a group consisting of a naphthol, a naphthylamine, a naphthol-sulphonic acid and a naphthylamine-sulphonic acid. 1 2. An orange disa'zo dyestuif obtainable by coupling tetrazotized m m-tolidine with one molecular proportion of Z-methyl-aminonaphthalene 'i sulphonicJacid and with one molecular proportion of a naphthalene compound of the group consisting of 2 naphthol, '2-naphthol-sulphonic acids, and 2-naphthylamine-G-sulphonic acid. i

3. :An. orange disazodyestufi represented by the following general formula r on, OOONa "1 I I so.NaT 7 lp Aln orange disazo dyestu'flf represented loythe following gen'eral formula I I on, COONa HzN 1 l V A i H;

' 7 SO;Na .,I

' 5. The process of preparing an orange disazo dyestufi which comprises coupling-tetrazotized m :'m-tolidine withone molecular proportion. of 2 methyl amino 4 naphthalene-7-sulphonic acid and with one molecular proportion of a naphthalene compound of the group consisting of Q-naphthol, 2-naph- -thol-sulphonic acids, and Z-naphthyIamine- 6-sulphonic acid." I 1 I 6. The process of preparing an orange disazo dyestuff which comprises coupling "tetrazotized 4: 1 diamino 12 2'- dimethyl diphenyl in alkaline solution with one'molecular proportion of salicylic acid and one molecular proportion of 2-naphthol-6-sulphonic acid. v i

'7; The process of preparing an orange disazo dyestufi which comprises coupling tetrazotized, i F-diamino-EZ: 2-dimethyl-diphenyl in alkaline solution with one molecular portion of salicylic acid-and one molecular proportion of 2-naphthylamine-6-sul-" phonic acid. 7 i

V ,8. A disazo dyestuif obtainable by coupling tetrazoti'zed'mz'm' tolidine with one molecular proportion ofa compound of the group consistingof salicylic acid and a 130 methyl-2maphthyl-amine-'Z-sulphonic= acid and with one molecular proportion of a,

naphthalene compound of the group consisting of 2-naphth01, 2-naphtho1-su1phonic acids, and Q-naphthyl amine-fi-esulphonic acids. L

In testimonlya whereof, I aflix my signature.

AINALD BRIGHTMAN. 

